It is known in vehicle seat belt systems to employ a continuous loop of belt having a latch plate assembly slidable therealong to adjust the relative restraint lengths of the lap and shoulder belt portions. It is also known to provide a retractor mounting one end of the belt, preferably the shoulder belt end, to wind the continuous loop belt to a stored position extending generally vertically between an upper anchor mounting the shoulder belt end on the vehicle body and a lower anchor mounting the lap belt end on the vehicle body. The belt may be unwound from the retractor and extended across the occupant torso to engage the latch plate assembly in a buckle suitably mounted on a vehicle body inboard the occupant seat.
The latch plate assembly most commonly used in conjunction with the aforedescribed continuous loop single retractor seat belt system is comprised of a housing having a stamping with a base wall and upturned flanges at the sides of the base wall. Angled slots provided in the upturned flanges slidably mount a lock bar. A rectangular aperture provided in the base wall permits the continuous loop belt to enter the housing, wrap around the bar, and then exit back through the rectangular opening. This latch plate assembly is oriented with the base wall adjacent the occupant torso and the flanges directed away from the occupant torso When the latch plate assembly is engaged in the buckle, the lap belt and shoulder belt portions are oriented generally colinear with one another and the tension on the lap belt induces the lock bar to slide to the end of the slot furthest from the buckle, the belt is cinched so that the transference of the belt through the latch belt assembly is limited to the direction in which the lap belt length is shortened. When the buckle is unbuckled, the retractor winds the continuous loop belt to a generally vertical condition, running generally between the upper and lower anchors. A convoluted pathway of the belt through the rectangular opening in the base wall and thence around the lock bar effectively prevents the latch plate assembly from sliding on the belt unless the occupant grips the belt and pulls the belt through the latch plate assembly.
It would be desirable to provide a latch plate assembly in which the latch plate would be free falling relative to the belt when in a stored position so that the force of gravity would induce the latch plate assembly to slide vertically down along the stored belt to a position on the seat or adjacent the lower anchor where it can be predictably gripped by the occupant during a subsequent attempt to don the seat belt.